Management of Wheat Powdery Mildew using Cow Urine based Plant Extracts

Wheat powdery mildew (PM) caused by Blumeria graminis f.sp. tritici (Bgt) is a disease of global occurrence and importance inflicting huge reduction in yield. Most of the varieties, grown commercially in epidemiologically important areas of India, are susceptible to it and application of fungicides provide a short-term effective means for its management. In present study cow urine-based leaf extracts of eight commonly available plants were evaluated for the management of the disease under in vitro, greenhouse and field conditions during 2018-19 at CSK Himachal Pradesh Agricultural University, Palampur, a hot spot for the disease. All the treatments resulted in significantly less spore germination at 5 to 20 per cent concentration as compared with no treatment check. Maximum spore germination inhibition of 78.87, 73.01 and 71.35 per cent was recorded in plant extract of Azadirachta indica, Calotropis gigantia and Justicia adhatoda, respectively under in vitro conditions. The interaction effects of concentration and treatments were significant at 72 hoursof incubation which indicated that treatment effect varied with the concentration. A. indica @ 20 per cent was highly effective both as preventive and curative treatment as foliar sprays under greenhouse conditions. The least per cent disease index (PDI) of 19.05 per cent with disease control of 85.28 per cent was recorded in leaf extracts of C. gigantia followed by J. adhatoda (21.39%) and A. indica (25.74%). The highest grain yield of 34.63 q/ha with 39.82 per cent increase over the untreated check was with C. gigantia followed by J. adhatoda and A. indica. The highest net profit of Rs.14649 per ha with cost benefit ratio of 1:5.2.